xref: /illumos-gate/usr/src/lib/print/libpapi-lpd/common/lpd-port.c (revision 7a088f03b431bdffa96c3b2175964d4d38420caa)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  *
26  */
27 
28 /* $Id: lpd-port.c 155 2006-04-26 02:34:54Z ktou $ */
29 
30 #include <config-site.h>
31 
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <unistd.h>
35 #include <sys/types.h>
36 #include <sys/stat.h>
37 #include <fcntl.h>
38 #include <stdarg.h>
39 #include <string.h>
40 #include <signal.h>
41 #include <sys/socket.h>
42 #include <netinet/in.h>
43 #include <arpa/inet.h>
44 #include <netdb.h>
45 #include <errno.h>
46 #include <syslog.h>
47 #include <values.h>
48 #include <stropts.h>	/* for sendfd */
49 #include <sys/uio.h>	/* for sendmsg stuff */
50 #include <pwd.h>
51 #include <sys/sendfile.h>
52 #include <ctype.h>
53 #ifdef HAVE_PRIV_H
54 #include <priv.h>
55 #endif
56 
57 #ifndef	JOB_ID_FILE
58 #define	JOB_ID_FILE	"/var/run/rfc-1179.seq"
59 #endif	/* JOB_ID_FILE */
60 
61 static int
62 sendfd(int sockfd, int fd)
63 {
64 	syslog(LOG_DEBUG, "sendfd(%d, %d)", sockfd, fd);
65 
66 #if defined(sun) && defined(unix) && defined(I_SENDFD)
67 	return (ioctl(sockfd, I_SENDFD, fd));
68 #else
69 	struct iovec	iov[1];
70 	struct msghdr	msg;
71 #ifdef CMSG_DATA
72 	struct cmsghdr cmp[1];
73 	char buf[2];    /* send/recv 2 byte protocol */
74 
75 	iov[0].iov_base = buf;
76 	iov[0].iov_len = 2;
77 
78 	cmp[0].cmsg_level = SOL_SOCKET;
79 	cmp[0].cmsg_type = SCM_RIGHTS;
80 	cmp[0].cmsg_len = sizeof (struct cmsghdr) + sizeof (int);
81 	* (int *)CMSG_DATA(cmp) = fd;
82 
83 	buf[1] = 0;
84 	buf[0] = 0;
85 	msg.msg_control = cmp;
86 	msg.msg_controllen = sizeof (struct cmsghdr) + sizeof (int);
87 #else
88 	iov[0].iov_base = NULL;
89 	iov[0].iov_len = 0;
90 	msg.msg_accrights = (caddr_t)&fd;
91 	msg.msg_accrights = sizeof (fd);
92 #endif
93 	msg.msg_iov = iov;
94 	msg.msg_iovlen = 1;
95 	msg.msg_name = NULL;
96 	msg.msg_namelen = 0;
97 
98 	return (sendmsg(sockfd, &msg, 0));
99 #endif
100 }
101 
102 static void
103 null(int i)
104 {
105 }
106 
107 static int
108 sock_connect(int sock, char *host, int timeout)
109 {
110 	struct hostent *hp;
111 	struct servent *sp;
112 #if defined(HAVE_GETIPNODEBYNAME) && defined(HAVE_RRESVPORT_AF)
113 	struct sockaddr_in6 sin;
114 #else
115 	struct sockaddr_in sin;
116 #endif
117 	static void (*old_handler)();
118 	int	err, error_num;
119 	unsigned timo = 1;
120 
121 	/*
122 	 * Get the host address and port number to connect to.
123 	 */
124 	if (host == NULL) {
125 		return (-1);
126 	}
127 
128 	/* linux style NULL usage */
129 	(void) memset((char *)&sin, (int)NULL, sizeof (sin));
130 
131 #if defined(HAVE_GETIPNODEBYNAME) && defined(HAVE_RRESVPORT_AF)
132 	if ((hp = getipnodebyname(host, AF_INET6, AI_DEFAULT,
133 	    &error_num)) == NULL) {
134 		errno = ENOENT;
135 		return (-1);
136 	}
137 	(void) memcpy((caddr_t)&sin.sin6_addr, hp->h_addr, hp->h_length);
138 	sin.sin6_family = hp->h_addrtype;
139 #else
140 	if ((hp = gethostbyname(host)) == NULL) {
141 		errno = ENOENT;
142 		return (-1);
143 	}
144 
145 	(void) memcpy((caddr_t)&sin.sin_addr, hp->h_addr, hp->h_length);
146 	sin.sin_family = hp->h_addrtype;
147 #endif
148 
149 	if ((sp = getservbyname("printer", "tcp")) == NULL) {
150 		errno = ENOENT;
151 		return (-1);
152 	}
153 
154 #if defined(HAVE_GETIPNODEBYNAME) && defined(HAVE_RRESVPORT_AF)
155 	sin.sin6_port = sp->s_port;
156 #else
157 	sin.sin_port = sp->s_port;
158 #endif
159 
160 retry:
161 	old_handler = signal(SIGALRM, null);
162 	(void) alarm(timeout);
163 
164 	if (connect(sock, (struct sockaddr *)&sin, sizeof (sin)) < 0) {
165 		(void) alarm(0);
166 		(void) signal(SIGALRM, old_handler);
167 
168 		if (errno == ECONNREFUSED && timo <= 16) {
169 			(void) sleep(timo);
170 			timo *= 2;
171 			goto retry;
172 		}
173 
174 		return (-1);
175 	}
176 
177 	(void) alarm(0);
178 	(void) signal(SIGALRM, old_handler);
179 	return (sock);
180 }
181 
182 static int
183 next_job_id()
184 {
185 	int fd, result = getpid() % 1000;
186 
187 	/* gain back enough privilege to open the id file */
188 #ifdef	PRIV_ALLSETS
189 	if ((priv_set(PRIV_ON, PRIV_EFFECTIVE,
190 	    PRIV_FILE_DAC_READ, PRIV_FILE_DAC_WRITE, NULL)) < 0) {
191 		syslog(LOG_ERR, "lpd_port:next_job_id:priv_set fails: : %m");
192 		return (-1);
193 	}
194 #else
195 	seteuid(0);
196 #endif
197 
198 	/* open the sequence file */
199 	if (((fd = open(JOB_ID_FILE, O_RDWR)) < 0) && (errno == ENOENT))
200 		fd = open(JOB_ID_FILE, O_CREAT|O_EXCL|O_RDWR, 0644);
201 
202 	syslog(LOG_DEBUG, "sequence file fd: %d", fd);
203 
204 	/* drop our privilege again */
205 #ifdef	PRIV_ALLSETS
206 	/* drop file access privilege */
207 	priv_set(PRIV_OFF, PRIV_PERMITTED,
208 	    PRIV_FILE_DAC_READ, PRIV_FILE_DAC_WRITE, NULL);
209 #else
210 	seteuid(getuid());
211 #endif
212 
213 	if (fd >= 0) {
214 		/* wait for a lock on the file */
215 		if (lockf(fd, F_LOCK, 0) == 0) {
216 			char buf[8];
217 			int next;
218 
219 			/* get the current id */
220 			(void) memset(buf, 0, sizeof (buf));
221 			if (read(fd, buf, sizeof (buf)) > 0)
222 				result = atoi(buf);
223 
224 			next = ((result < 999) ? (result + 1) : 0);
225 
226 			/* store the next id in the file */
227 			snprintf(buf, sizeof (buf), "%.3d", next);
228 			if ((lseek(fd, 0, SEEK_SET) == 0) &&
229 			    (ftruncate(fd, 0) == 0))
230 				write(fd, buf, strlen(buf));
231 		}
232 		close(fd);
233 	}
234 	syslog(LOG_DEBUG, "next_job_id() is %d", result);
235 
236 	return (result);
237 }
238 
239 static int
240 reserved_port()
241 {
242 	int result = -1;
243 	int port;
244 
245 	/* gain back enough privilege to open a reserved port */
246 #ifdef	PRIV_ALLSETS
247 	if ((priv_set(
248 	    PRIV_ON, PRIV_EFFECTIVE, PRIV_NET_PRIVADDR, NULL)) != 0) {
249 		syslog(LOG_ERR, "priv_set fails for net_privaddr %m");
250 		return (-1);
251 	}
252 #else
253 	seteuid(0);
254 #endif
255 
256 #if defined(HAVE_GETIPNODEBYNAME) && defined(HAVE_RRESVPORT_AF)
257 	port = 0;	/* set to 0, rresvport_af() will find us one. */
258 	result = rresvport_af(&port, AF_INET6);
259 #else
260 	port = IPPORT_RESERVED - 1;
261 	while (((result = rresvport(&port)) < 0) && (port >= 0))
262 		port--;
263 #endif
264 
265 	/* drop our privilege again */
266 #ifdef	PRIV_ALLSETS
267 	priv_set(PRIV_OFF, PRIV_PERMITTED, PRIV_NET_PRIVADDR, NULL);
268 #else
269 	seteuid(getuid());
270 #endif
271 
272 	return (result);
273 }
274 
275 static char *
276 get_user_name()
277 {
278 	static struct passwd *p = NULL;
279 
280 	if ((p = getpwuid(getuid())) != NULL)
281 		return (p->pw_name);
282 	else
283 		return ("unknown");
284 }
285 
286 static void
287 add_args(int ac, char **av, char *buf, size_t len)
288 {
289 	while (ac--) {
290 		strlcat(buf, " ", len);
291 		strlcat(buf, *(av++), len);
292 	}
293 }
294 
295 static int
296 massage_control_data(char *data, int id)
297 {
298 	char *line, *iter = NULL;
299 	char *ptr, *datacpy;
300 	char host[BUFSIZ];
301 	int host_present = 0;
302 
303 	if (gethostname(host, sizeof (host)) != 0)
304 		return (-1);
305 
306 	if ((datacpy = strdup(data)) == NULL) {
307 		return (-1);
308 	}
309 
310 	for (ptr = strtok_r(datacpy, "\n", &iter); ptr != NULL;
311 	    ptr = strtok_r(NULL, "\n", &iter)) {
312 
313 		if (ptr[0] == 'H') {
314 			if (strncmp(++ptr, host, strlen(host)) != 0) {
315 				free(datacpy);
316 				return (-1);
317 			}
318 			host_present = 1;
319 		} else if ((ptr[0] == 'P') || (ptr[0] == 'L')) {
320 			/* check the user name */
321 			uid_t uid = getuid();
322 			struct passwd *pw;
323 			int len;
324 
325 			if (uid == 0) {	/* let root do what they want */
326 				continue;
327 			}
328 			if ((pw = getpwuid(uid)) == NULL) {
329 				free(datacpy);
330 				return (-1);	/* failed */
331 			}
332 			len = strlen(pw->pw_name);
333 			if ((strncmp(++ptr, pw->pw_name, len) != 0)) {
334 				free(datacpy);
335 				return (-1);	/* failed */
336 			}
337 		} else if ((islower(ptr[0]) != 0) || (ptr[0] == 'U')) {
338 			/* check/fix df?XXXhostname */
339 			ptr++;
340 
341 			if (strlen(ptr) < 6) {
342 				free(datacpy);
343 				return (-1);
344 			}
345 			if ((ptr[0] == 'd') && (ptr[1] == 'f') &&
346 			    (ptr[3] == 'X') && (ptr[4] == 'X') &&
347 			    (ptr[5] == 'X')) {
348 				ptr[3] = '0' + (id / 100) % 10;
349 				ptr[4] = '0' + (id / 10) % 10;
350 				ptr[5] = '0' + id % 10;
351 
352 				if (strncmp(&ptr[6], host, strlen(host)) != 0) {
353 					free(datacpy);
354 					return (-1);
355 				}
356 			} else {
357 				free(datacpy);
358 				return (-1);
359 			}
360 		}
361 
362 	}
363 	free(datacpy);
364 
365 	if (!host_present) {
366 		return (-1);
367 	}
368 
369 	return (1);
370 }
371 
372 static int
373 send_lpd_message(int fd, char *fmt, ...)
374 {
375 	char buf[BUFSIZ];
376 	size_t size;
377 	va_list ap;
378 
379 	va_start(ap, fmt);
380 	size = vsnprintf(buf, sizeof (buf), fmt, ap);
381 	va_end(ap);
382 	if (size == 0)
383 		size = 1;
384 
385 	syslog(LOG_DEBUG, "lpd_messsage(%d, %s)", fd, buf);
386 
387 	if (write(fd, buf, size) != size) {
388 		errno = EIO;
389 		return (-1);
390 	}
391 
392 	if ((read(fd, buf, 1) != 1) || (buf[0] != 0))
393 		return (-1);
394 
395 	return (0);
396 }
397 
398 static int
399 send_data_file(int sock, char *dfname, char *name)
400 {
401 	size_t len;
402 	off_t off = 0;
403 	struct stat st;
404 	char buf[32];
405 	int fd = -1;
406 
407 	if (strcmp(name, "standard input") != 0) {
408 		if ((fd = open(name, O_RDONLY)) < 0)
409 			return (-1);
410 
411 		if (fstat(fd, &st) < 0)
412 			return (-1);
413 	} else
414 		st.st_size = MAXINT; /* should be 0 */
415 
416 	/* request data file transfer, read ack/nack */
417 	errno = ENOSPC;
418 	if (send_lpd_message(sock, "\003%d %s\n", st.st_size, dfname) < 0)
419 		return (-1);
420 
421 	if (fd != -1) {
422 		/* write the data */
423 		if (sendfile(sock, fd, &off, st.st_size) != st.st_size)
424 			return (-1);
425 		close(fd);
426 
427 		/* request ack/nack after the data transfer */
428 		errno = EIO;
429 		if (send_lpd_message(sock, "") < 0)
430 			return (-1);
431 	}
432 
433 	return (0);
434 }
435 
436 static int
437 send_control_file(int sock, char *data, int id)
438 {
439 	int len;
440 	char buf[BUFSIZ];
441 	char *ptr, *iter = NULL;
442 	char *datacpy = NULL;
443 	char *host = NULL;
444 
445 	len = strlen(data);
446 
447 	if ((datacpy = strdup(data)) == NULL)
448 		return (-1);
449 
450 	syslog(LOG_DEBUG, "cfA: %s\n", datacpy);
451 
452 	for (ptr = strtok_r(datacpy, "\n", &iter); ptr != NULL;
453 	    ptr = strtok_r(NULL, "\n", &iter)) {
454 
455 		if (ptr[0] != 'H')
456 			continue;
457 
458 		ptr++;
459 		host = ptr;
460 		syslog(LOG_DEBUG, "hostname: %s\n", host);
461 	}
462 
463 	free(datacpy);
464 
465 	/* request data file transfer, read ack/nack */
466 	errno = ENOSPC;
467 	if (send_lpd_message(sock, "\002%d cfA%.3d%s\n", len, id, host) < 0)
468 		return (-1);
469 
470 	/* write the data */
471 	if (write(sock, data, len) != len)
472 		return (-1);
473 
474 	/* request ack/nack after the data transfer */
475 	errno = EIO;
476 	if (send_lpd_message(sock, "") < 0)
477 		return (-1);
478 
479 	return (0);
480 }
481 
482 
483 static int
484 submit_job(int sock, char *printer, int job_id, char *path)
485 {
486 	struct stat st;
487 	int current = 0;
488 	off_t off = 0;
489 	char *metadata = NULL;
490 	char *ptr, *iter = NULL;
491 	int fd, err;
492 	int sent_files = 0;
493 	char buf[BUFSIZ];
494 	size_t len;
495 
496 	/* open the control file */
497 	if ((fd = open(path, O_RDONLY)) < 0) {
498 		syslog(LOG_ERR, "submit_job(%d, %s, %d, %s): open(): %m",
499 		    sock, printer, job_id, path);
500 		return (-1);
501 	}
502 
503 	/* get the size of the control file */
504 	if (fstat(fd, &st) < 0) {
505 		syslog(LOG_ERR, "submit_job(%d, %s, %d, %s): fstat(): %m",
506 		    sock, printer, job_id, path);
507 		close(fd);
508 		return (-1);
509 	}
510 
511 	/* allocate memory for the control file */
512 	if ((metadata = calloc(1, st.st_size + 1)) == NULL) {
513 		syslog(LOG_ERR, "submit_job(%d, %s, %d, %s): calloc(): %m",
514 		    sock, printer, job_id, path);
515 		close(fd);
516 		return (-1);
517 	}
518 
519 	/* read in the control file */
520 	if (read(fd, metadata, st.st_size) != st.st_size) {
521 		syslog(LOG_ERR, "submit_job(%d, %s, %d, %s): read(): %m",
522 		    sock, printer, job_id, path);
523 		free(metadata);
524 		close(fd);
525 		return (-1);
526 	}
527 
528 	/* massage the control file */
529 	if (massage_control_data(metadata, job_id) < 0) {
530 		/* bad control data, dump the job */
531 		syslog(LOG_ALERT,
532 		    "bad control file, possible subversion attempt");
533 		free(metadata);
534 		errno = EINVAL;
535 		close(fd);
536 		return (-1);
537 	}
538 
539 	/* request to transfer the job */
540 	if (send_lpd_message(sock, "\002%s\n", printer) < 0) {
541 		/* no such (or disabled) queue, got to love rfc-1179 */
542 		errno = ENOENT;
543 		return (-1);
544 	}
545 
546 	/* send the control data */
547 	if (send_control_file(sock, metadata, job_id) < 0) {
548 		err = errno;
549 		write(sock, "\001\n", 2); /* abort */
550 		errno = err;
551 		return (-1);
552 	}
553 
554 	/* walk the control file sending the data files */
555 	for (ptr = strtok_r(metadata, "\n", &iter); ptr != NULL;
556 	    ptr = strtok_r(NULL, "\n", &iter)) {
557 		char *name = NULL;
558 
559 		if (ptr[0] != 'U')
560 			continue;
561 
562 		name = strtok_r(NULL, "\n", &iter);
563 		if (name[0] != 'N')
564 			continue;
565 
566 		ptr++;
567 		name++;
568 
569 		if (send_data_file(sock, ptr, name) < 0) {
570 			err = errno;
571 			write(sock, "\001\n", 2); /* abort */
572 			errno = err;
573 			return (-1);
574 		}
575 		if (strcmp(name, "standard input") != 0)
576 			sent_files++;
577 	}
578 
579 	/* write back the job-id */
580 	err = errno;
581 	if ((fd = open(path, O_WRONLY)) >= 0) {
582 		ftruncate(fd, 0);
583 		write(fd, &job_id, sizeof (job_id));
584 		close(fd);
585 	}
586 	errno = err;
587 
588 	if (sent_files != 0) {
589 		err = errno;
590 		close(sock);
591 		errno = err;
592 	}
593 
594 	return (0);
595 }
596 static int
597 query(int fd, char *printer, int ac, char **av)
598 {
599 	char buf[BUFSIZ];
600 	int rc, len;
601 
602 	/* build the request */
603 	snprintf(buf, sizeof (buf), "\04%s", printer);
604 	add_args(ac, av, buf, sizeof (buf));
605 	strlcat(buf, "\n", sizeof (buf));
606 	len = strlen(buf);
607 
608 	if (((rc = write(fd, buf, len)) >= 0) && (rc != len)) {
609 		errno = EMSGSIZE;
610 		rc = -1;
611 	} else
612 		rc = 0;
613 
614 	return (rc);
615 }
616 
617 static int
618 cancel(int fd, char *printer, int ac, char **av)
619 {
620 	char buf[BUFSIZ];
621 	int rc, len;
622 
623 	/* build the request */
624 	snprintf(buf, sizeof (buf), "\05%s %s", printer, get_user_name());
625 	add_args(ac, av, buf, sizeof (buf));
626 	strlcat(buf, "\n", sizeof (buf));
627 	len = strlen(buf);
628 
629 	if (((rc = write(fd, buf, len)) >= 0) && (rc != len)) {
630 		errno = EMSGSIZE;
631 		rc = -1;
632 	} else
633 		rc = 0;
634 
635 	return (rc);
636 }
637 
638 static void
639 usage(char *program)
640 {
641 	char *name;
642 
643 	setreuid(getuid(), getuid());
644 
645 	if ((name = strrchr(program, '/')) == NULL)
646 		name = program;
647 	else
648 		name++;
649 
650 	fprintf(stderr, "usage:\t%s -H host [-t timeout] -s queue control ]\n",
651 	    name);
652 	fprintf(stderr, "\t%s -H host [-t timeout] -c queue [user|job ...]\n",
653 	    name);
654 	fprintf(stderr, "\t%s -H host [-t timeout] -q queue [user|job ...]\n",
655 	    name);
656 	exit(EINVAL);
657 }
658 
659 /*
660  * The main program temporarily loses privilege while searching the command
661  * line arguments.  It then allocates any resources it need privilege for
662  * job-id, reserved port.  Once it has the resources it needs, it perminently
663  * drops all elevated privilege.  It ghen connects to the remote print service
664  * based on destination hostname.  Doing it this way reduces the potenential
665  * opportunity for a breakout with elevated privilege, breakout with an
666  * unconnected reserved port, and exploitation of the remote print service
667  * by a calling program.
668  */
669 int
670 main(int ac, char *av[])
671 {
672 	enum { OP_NONE, OP_SUBMIT, OP_QUERY, OP_CANCEL } operation = OP_NONE;
673 	int fd, c, timeout = 0, exit_code = 0;
674 	char *host = NULL, *queue = NULL;
675 	uid_t uid = getuid();
676 #ifdef	PRIV_ALLSETS
677 	priv_set_t *saveset = NULL;
678 #endif
679 
680 	openlog("lpd-port", LOG_PID, LOG_LPR);
681 
682 #ifdef	PRIV_ALLSETS
683 
684 	/* lose as much as we can perminently and temporarily drop the rest. */
685 
686 	if ((saveset = priv_str_to_set("PRIV_NET_PRIVADDR,"
687 	    "PRIV_FILE_DAC_READ,PRIV_FILE_DAC_WRITE,",
688 	    ",", (const char **)NULL)) == NULL) {
689 		syslog(LOG_ERR,
690 		    "lpd_port: priv_str_to_set saveset failed: %m\n");
691 		return (-1);
692 	}
693 
694 	if ((setppriv(PRIV_SET, PRIV_PERMITTED, saveset)) < 0) {
695 		syslog(LOG_ERR, "lpd_port:setppriv:priv_set failed: %m");
696 		return (-1);
697 	}
698 
699 	/*
700 	 * These privileges permanently dropped in next_job_id() and
701 	 * reserved_port()
702 	 */
703 
704 	if ((setppriv(PRIV_OFF, PRIV_EFFECTIVE, saveset)) < 0) {
705 		syslog(LOG_ERR, "lpd_port:setppriv:priv_off failed: %m");
706 		return (-1);
707 	}
708 
709 	priv_freeset(saveset);
710 
711 	syslog(LOG_DEBUG, "using privs");
712 #else
713 
714 	syslog(LOG_DEBUG, "no  privs");
715 	seteuid(uid);
716 #endif
717 
718 	while ((c = getopt(ac, av, "H:t:c:q:s:")) != EOF) {
719 		switch (c) {
720 		case 'H':
721 			host = optarg;
722 			break;
723 		case 't':
724 			timeout = atoi(optarg);
725 			break;
726 		case 'c':
727 			if (operation != OP_NONE)
728 				usage(av[0]);
729 			operation = OP_CANCEL;
730 			queue = optarg;
731 			break;
732 		case 'q':
733 			if (operation != OP_NONE)
734 				usage(av[0]);
735 			operation = OP_QUERY;
736 			queue = optarg;
737 			break;
738 		case 's':
739 			if (operation != OP_NONE)
740 				usage(av[0]);
741 			operation = OP_SUBMIT;
742 			queue = optarg;
743 			break;
744 		default:
745 			usage(av[0]);
746 			/* does not return */
747 		}
748 	}
749 
750 	if ((host == NULL) || (queue == NULL) || (timeout < 0) ||
751 	    (operation == OP_NONE))
752 		usage(av[0]);
753 
754 	if (operation == OP_SUBMIT)	/* get a job-id if we need it */
755 		if ((c = next_job_id()) < 0) {
756 			syslog(LOG_ERR, "lpd_port:main:next_job_id fails");
757 			return (-1);
758 		}
759 
760 	if ((fd = reserved_port()) < 0) {
761 		syslog(LOG_ERR, "reserved_port() failed %m");
762 		return (errno);
763 	}
764 
765 	/*
766 	 * we no longer want or need any elevated privilege, lose it all
767 	 * permanently.
768 	 */
769 
770 	setreuid(uid, uid);
771 
772 	/* connect to the print service */
773 	if ((fd = sock_connect(fd, host, timeout)) < 0)
774 		return (errno);
775 
776 	/* perform the requested operation */
777 	switch (operation) {
778 	case OP_SUBMIT:	/* transfer the job, close the fd */
779 		if (submit_job(fd, queue, c, av[optind]) < 0)
780 			exit_code = errno;
781 		break;
782 	case OP_QUERY:	/* send the query string, return the fd */
783 		if (query(fd, queue, ac - optind, &av[optind]) < 0)
784 			exit_code = errno;
785 		break;
786 	case OP_CANCEL:	/* send the cancel string, return the fd */
787 		if (cancel(fd, queue, ac - optind, &av[optind]) < 0)
788 			exit_code = errno;
789 		break;
790 	default:	/* This should never happen */
791 		exit_code = EINVAL;
792 	}
793 
794 
795 	/* if the operation succeeded, send the fd to our parent */
796 	if ((exit_code == 0) && (sendfd(1, fd) < 0)) {
797 		char buf[BUFSIZ];
798 
799 		exit_code = errno;
800 
801 		/* sendfd() failed, dump the socket data for the heck of it */
802 		while ((c = read(fd, buf, sizeof (buf))) > 0)
803 			write(1, buf, c);
804 	}
805 
806 	syslog(LOG_DEBUG, "exit code: %d", exit_code);
807 	return (exit_code);
808 }
809